Anion exchange membranes (AEMs) sill remains a povital issue such as low ion conductivity, which hinders the practical applications. Therefore, constructing cross-linking structure in AEMs is considered as an effective strategy to balance the comprehensive properties including chemical stability and ion conductivity. However, the cross-linking may hinder the ion transport and decrease the ion conductivity unsatisfactorily. Herein we prepared highly ion conducive quaternized polysulfone (QPSU)-based AEMs (CQPSU-X-rGO) cross-linked by reduced graphene oxide (rGO) functionalized with different-chain length small molecules. The cross-linked QPSU AEMs (CQPSU-n) with organic small molecules as cross-linkers were also prepared to serve as control samples. Compared with AEMs cross-linked by short-chain cross-linkers, the cross-linked membranes with elastic long-chain cross-linkers (PTMHDA) and their modified rGO (LrGO) displayed higher ion conductivity due to the generation of more quaternary ammonium groups and nanophase separated morphology. Especially, the functionalized rGO-cross-linked composite membranes (CQPSU-X-LrGO and CQPSU-X-SrGO) exhibited better conductivity and chemical stability as compared with cross-linked polymer membranes (t-CQPSU-n and p-CQPSU-n) with small molecule cross-linkers. The highest ion conductivity was achieved for rGO-cross-linked AEMs (CQPSU-2%-LrGO, sigma(-)(O)(H) = 139.7 mS/cm at 80 degrees C). Thus, the functionalized rGO has been demonstrated to be a potential cross-linker and filler for preparing cross-linked AEMs with improved properties.